@Michael Plaks Kudos to you for creating this post and countless others that provide infinite value to the real estate investor community!

I understand the potential Infinite return of BRRRR, but if I spend x effort and y dollars on a value add, I want it to add as much value as possible. 

It will only cash flow about $150/door/month, but I tell you this to point out that cash-on-cash returns are nice to analyze, but I am getting to the point that something that cant be an infinite cash-on-cash return at some point in the near future just doesnt sound that appealing.  

its mostly focused on retail, but the inputs are infinitely adjustable for whatever asset you are going after.   

If you've enjoyed a lot of appreciation in the value of your primary home, you may want to start a timer to sell before losing the "lived in the house for 2 of the last 5 years" capital gains exemption (limited; not infinite, but big).  

You have an infinite ROI bc the property was free, but you are generating a 4% annual return ($100x12) on your 30k equity position. b.

That to me is the simplest deal structure and the least "risk to you" as you aren't waiting for the final home to complete to be paid, as I understand it most construction loans close on the "dirt" up front....although like everything in real estate its infinitely negotiable and changeable.  

However if I do a BRRRR I can achieve infinite return by extracting all of my investment.

If I had infinite capital it would still likely take me another 6-7 years to buy 150 units.

Money can be infinite but time is not. 48 years old now.